Bobbin



Oct. l28, 1952 T, E, SE1-NER TAL 2,615,650

BOBBIN n Filed Oct. 25, 1948 INVENTORS SE Thon/.5 ezner @we BY Josep/ R. msewa Patented Oct. 28, 1952 UNITED STATES PATENT oFFlcE BOBBIN Thomas E. Betner and Joseph R. Townsend,

Wayne, Pa., assignors to Sonoco Products Company, a corporation of South Carolina Application October 23, 1948, Serial No. 56,234

2 Claims.

This invention relates to bobbins used with textile. machines such as spinning machines for spooling, twisting or winding of cotton, Wool, nylon and other natural or synthetic yarns.

In use, as each bobbin is inv turn lled,fit is doffed or pulled off its rapidly revolving driving spindle and another empty bobbin is shoved into place on the spindle. Also when the yarn breaks, the operator or doifer must lift the bobbin from the revolving spindle, tie the broken ends of the thread and place the bobbin back on the spindle. It is essential that the bobbins be releasable by a light pull as otherwise it may be necessary to shut down the entire machine to avoid injury to the doffer. When it is recalled a single machine may have hundreds of spindles and that breakage of the threads is a frequent occurrence, it is apparent that 'the loss of operating time becomes intolerable if jammed bobbinsenforce frequent stoppage. Moreover, the bobbins or the yarn thereon are usually badly damaged by forcible removal of jammed bobbins.

At present, there are in use a variety of paper or wood bobbins which, though when new are fairly satisfactory from the standpoint of easy dofing, are unsatisfactory for other reasons including their short useful life and their contamination of yarn by moisture and dye absorbed by the bobbin. In general, the short useful life of such bobbins is due to their dimensional instability; they are easily fractured, warped, worn, deformed or broken and so shortly lose their easy doiing characteristic. Consequently, use of such bobbins is accompanied by high replacement costs. An even more serious difliculty is that even though the deformation or denting of a wooden or paper bobbin may not be noticeable, it is so out of balance that the expensive spindle bearings are worn out in a short time. Attempts to use bobbins of aluminum, pressed steel, brass and the like to obtain dimensional stability have not proved commercially successful because of doffing diiliculties.

In accordance with the present invention, the characteristics of easy doffing and dimensional stability are both obtained by making the bobbin of material, preferably molded Bakelite or other thermosetting material, which is sufliciently tough to resist deformation despite rough handling and which' is impervious to moisture and dye. The dimensional stability of the bobbin insures long life ofv the spindle bearings, minimizing costv of their replacement and the incidental loss of operating time of the machine. To attain easy doning, the tapered bore of the bobbin is pref- 2 erably providedA with a plurality of projections such as splines or ribs, spaced internally ofthe bore and of progressively increasing height toward the smaller endof the bore. In all cases the spindle-engagingface or faces of the bobbinv lie inor dene a surface oi revolution whose apex angle is slightly greater than that of the bore taper. Within a rather limited range of diierence between the tapers, it is possible to insure a firm driving engagement between the spindle and the bobbin which, however, can be readily broken by a slight pull. More specifically, the aforesaid splines, ribs or equivalent are disposed near the small end of the bore of thebobbin above its center of gravity.

In some forms of the invention, thereis a second set of splines or ribs formed integrally at the larger end of the bore to provide firm nonslipping driving engagement between the bobbin and unspooling mechanism used with it. f

The invention further resides infeatures, of construction hereinafter described and claimed.

For a more detailed understanding of the invention and for illustration of a preferred embodiment thereof, reference yis madeto the accompanying drawings in which: n

Fig. 1 is any elevational View of the bobbin in part broken away to show its integral splines; 't

Fig. 2 is a section, on enlarged scale, takenon line 2-2 of Fig. 1; 1

Fig. 3 is a section, on enlarged scale, taken-.on line 3-3 of Fig; 1;

Fig. 4 is `a section, on enlarged scale,r` taken on line 4 4 of Fig. 1; and I n Fig. 5 is a partial view, in perspective; showing one of the tapered ribs of Fig. l.

Referring to the particular embodiment shown in Fig. l, the body l of the bobbin is a thin tubular shell, the taper of Whose bore closely matches that of the driving spindle with which it is to be used. Usually the driving spindleis ci metal although in some cases, the tapered portion thereof which engages the bobbin is of a suitably hard wood. Within the smaller end of thebobbin bore there is a set of projections or ribs 2,` preferably three or four in number, equally angularly spaced circumferentially of the borer and so tapered each is of increasing height toward the smaller end of the bore. The maximum height of the projections 2 is exaggerated, for purpose of illustration, in the drawings; actually in a preferred construction it is less than .050 inch. The important feature is that the ribs, splines, or equivalent, shall define a spindle-engaging surface of revolution which iscoaxial withthe bore and whose apex angle 3 is slightly greater than the angle of taper of the bore.

The difference between the angle of taper of the spindle-engaging surface of the bobbin and the taper angle of the spindle is quite critical in that if the difference is too slight it will be difllcult to doi the bobbin either initially or after a short period of use. On the other hand, if the difference between the angles is too great, there will be a strong tendency for the bobbin to oat on an air-cushion when dropped onto the spindle instead of effecting a rm driving engagement therewith. When it is recalled that the driving spindles rotate at speeds yof theorder of 8,000 revolutions per minute and higher; itis evident the operator should neither attempt to remove a jammed bobbin nor manually force aA floating bobbin into driving engagement with the spindle. Moreover, either operation, in the aggregate, involves a substantial loss of time. With theproper difference in the taper angles, the bobbin maybe released from the rapidly revolving spindle by a slight pull and yet firmly grabs'the spindle when dropped over. it. By wayA of example, the ribs 2 may be about an inch longand in that distance rise from their point of merger with the bobbin bore to about .025 inch.

Thebobbin body l and the ribs 2, or equivalent,

are preferably integrally formed of thermosetting material such as Bakelite, or other thermosetting-material in an injection transfer die machine or press. Such vmaterials are tough, resilient, Wear-resistant and are impervious to, as

well as immune to attack by, moisture and liquids` tovwhich exposed'in textile processes. The ribs 2 because of thermoset material yield slightly when the bobbin is dropped or tossed down over the spindle and so provide a iirm driving engagement without scoring or grooving the spindle'as would occur with metal ribs. The thermoset material also has high resiliency and wear resistance with .the result the ribs retain their shape after long continued used. In fact, bobbins so made have .retained their characteristics of easy doiiing and firm driving engagement after thousands of doilng operations. Though the vline contacts between the ribs and the spindle strongly resist relative rotation or angular slip, they vare readily broken by a light upward pull.' There` isl no "freezing of metal to metal or stickingdue to scoring of the spindle or bobbin; As the ribs'are formed integrally with the bobbin, it is insured that all bobbins shall have the same characteristics without need for any expensive machining. A

operations, and these characteristics are retained because of the dimensional stability of the bobbins.

An important additional advantage of the bobbin described is thatv it has been possiblei'to' increase the speed of the spindlesjbylO 'per-cent or more with correspondingly increased output of'the spinningv machines. Despite the-higher speed, there is no tendency-for the bobbins'- to slip. and no increase in wear ofthe spindle vbearings.: In this connection it should begnoted lthat the ribs 2 are above the center of gravity soA that at spindle speeds of 10,000 R. P. M. and higher, there is no tendency for the bobbin, empty or loaded, to wobble and so become-loose onv the spindle. The increase in output due to increased spindle speed is in addition to the increase of output due to the easy doiiing characteristic of the bobbin which alone is about or-^more without increase in spindle speed.'

Although the projections which engage the driving spindle are, for manufacturing and other reasons, preferably ribs, as shown in the drawings, they may be a plurality of spaced lands of other regular or irregular shape, such as dimples, whose spindle-engaging tips or faces all lie in or define a surface of revolution whose apex angle is slightly greater thanithe taper. of the bobbin bore.

As the surface of the bobbin is hard and smooth, the external or yarn-engaging surface may be provided with a plurality of grooves 4 to prevent the initial layers of yarn from slipping upwardly during the spooling operation. The grooves 4`are also formed concurrently with the molding ofthe body I and the ribs 2.

Because madeof hard, tough thermoset material, the bobbins retain their shape despite rough handling and are not bent, fractured or dented when subjected Yto the usual dropping and rough handling incident to theirV use.. Thus, excessive spindle wear due to inadvertentuse-of imperfectbobbins. is practically obviated; Moreover, bobbins so constructed'are not affected by exposure to highly humid and high-temperature conditions encountered in textile processesand do not retain dyefof one spooling `for contamination of the yarn of a subsequent spooling.

In many mills, the filled bobbins are unspooled by a Barker-Coleman machine having `fingers or dogs which engagethe inside of the'bobbin to preventits rotation. With the bobbin thus far described;. the inner surface is so smoothA and hard thatfsuch driving fingers cannot:mantain 'av rm-l engagement with the bobbin' withthe result thatitslips when subjected tothe loadof unspooling'with consequent breakage of the yarn. This diiiiculty did'not arise. with new paperv or wooden bobbins because they would 'deform Awhen -subjectedto the pressure ofgthe gripping fingers.

Such deformationlof thepaperor woodenbobbins was, however, usually more or less permanent which further limited their-useful life.

To maintain .'firm'engagement between the -di mensionally rigid ybobbin bodyi and the driving ngers `ofa Barker-Coleman machine, there are provided; at the larger'end-of the bore, a second series.- or. set of circumferentially `spaced-ribs 5 for engagement with thegripping fingers of the Barker-Coleman or similar unspoolingl machine. Thesey ribs need not be tapered and mayv extend inwardly of' the bore about.015'of an inch; they may, for. example, be about M5" wide and about ljinchflong. Alternatively/the inner bore'may bez-providedwith a. series. of slight depressions or grooves to catch the driving fingers. As these ribs or depressions are integrally formed during molding. ofthe body ofthe-fbobbin, no subsequent expensive machining operations are necessary.

As'above stated, in thepreferred form'lof'the invention the bobbin 'body'is of molded thermoset materialand the off-taper, spindle-engaging structure such as ribs 2, is formed integrally therewith. Less desirably, the bobbin body may v be of vpressed metal, such as steel, brassoraluminum, andl theI spindle-engaging structurev or structures either integrallyvformed during. the pressing-.operation or 'attached to the bobbin as byl spot-welding; or, the `bobbin body lmay be of paper-or wood and lthe off-taper spindle-engaging structure inserted therein. In all of such arrangements, as in the bobbin of Fig.' l, the spindle-engaging surface or surfaces of the bobbin should lie in or denne a surface of revolution coaxial with the bobbin and whoseapex-angle is slightly greater than the angle of taper of the spindle. However, such arrangements in general lack important features of the preferred construction: for example, the paper body bobbin with an off -taper insert is inherently dimensionally unstable, either initially or after short periods of use, with consequent shortenedv life of the spindle bearings.

It shall be understood the invention is not limited to the particular embodiment shown and that changes and modifications may be made within the scope of the appended claims.

What is claimed is:

1. A bobbin providing firm driving engagement with a tapered spindle of a textile machine and easily doffed therefrom, comprising a tubular body member having a bore adapting said body member for disposition over said spindle, and longitudinally extending axial ribs formed interiorly of said bore and spaced about said bore adjacent the upper end thereof for driving engagement with said spindle, said ribs defining at their inner faces a conical surface of revolution coaxial with the bore of said body member and having an apex angle that is slightly greater than the taper angle of said spindle.

2. A bobbin providing firm driving engagement with a tapered spindle of a textile machine and easily doffed therefrom, comprising a tubular body member having a tapered bore matching the spindle taper, longitudinally extending axial ribs formed interiorly of said bore and spaced regularly about said bore adjacent the upper end thereof, said ribs merging with the said bore at their lower ends and defining by their inner faces a conical surface of revolution coaxial with said bore and having an apex angle that is slightly greater than the taper angle of said spindle,.

whereby when said tubular body is disposed over said spindle said ribs are adapted for seating readily in driving engagement therewith while spacing the remaining tapered bore of said tubular body against freezing on said tapered spindle, and additional circumferentially spaced longitudinal ribs formed interiorly of said tubular body bore adjacent the lower end thereof for engagement on an unspooling mechanism, said additional ribs having a taper corresponding to the taper of said tubular body bore and the extending faces of said additional ribs having a raised height interiorly of said bore not exceeding the spacing of said bore from said spindle by said first mentioned ribs.

THOMAS E. BETNER. JOSEPH R. TOWNSEND.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Number Name Date 2,419,415 Morf Apr. 22, 1947 FQREIGN PATENTS Number Country Date 4,604 Great Britain Nov. 13, 1878 152,216 Switzerland Apr. 1, 1932 790,554 France Sept. 9, 1935 848,620 France July 31, 1939 

